Is Cianocobalamina (57 Co) [INN-Spanish] Safe in Breastfeeding

I am a breastfeeding mother and i want to know if it is safe to use Cianocobalamina (57 Co) [INN-Spanish]? Is Cianocobalamina (57 Co) [INN-Spanish] safe for nursing mother and child? Does Cianocobalamina (57 Co) [INN-Spanish] extracts into breast milk? Does Cianocobalamina (57 Co) [INN-Spanish] has any long term or short term side effects on infants? Can Cianocobalamina (57 Co) [INN-Spanish] influence milk supply or can Cianocobalamina (57 Co) [INN-Spanish] decrease milk supply in lactating mothers?

Information in this record refers to the use of Cianocobalamina (57 Co) [INN-Spanish] as a diagnostic agent. Limited data indicate that excretion of radioactivity into breastmilk following Cianocobalamina (57 Co) [INN-Spanish] is low and does not require withholding of breastfeeding after diagnostic use. However, to minimize the radiation dose to the infant, some authors suggest that previously saved milk could be substituted for one feeding at about 24 hours after the dose.[1] Mothers concerned about the level of radioactivity in their milk could ask to have it tested at a nuclear medicine facility at their hospital. When the radioactivity is at a safe level she may resume breastfeeding. A method for measuring milk radioactivity and determining the time when a mother can safely resume breastfeeding has been published.[2]